Microsoft mouse scrolling problem in Windows 7 V6.1 Build 7000

I use the Microsoft Wireless Laser Mouse 5000. The wheel produces little scrolling movement. I have gone into Mouse Properties and tried every avenue to increase the amount of movement to no avail. I have also uninstalled and reinstalled the mouse software to no avail.

Is this a known issue and is there any fix available? I'm running the x86 version. Thank you very much for any replies.

I have the same mouse. I hate the fact that you keep erroneously hitting the magnifying button. It's hard to avoid hitting it. The mouse is difficult to scroll on desktop, desk map or mouse pad. Wish the magnifying button was better positioned to avoid erroneous hits and my biggest issue is the scrolling on the desktop.
Can you help me for this?